The overhand knot is a type of knot. It is one of the most fundamental knots and forms the basis of many others including the Simple noose, overhand loop, angler's loop, and fisherman's knot. The overhand knot is very secure, to the point of jamming badly. It should be used if the knot is intended to be permanent (in fact, it is often used to prevent the end of a rope from unravelling).

Hagfish clean slime off themselves by twisting themselves this way.

The use of two overhand knots, one used as a stopper.

Tying

There are a number of ways to tie the Overhand knot.

Thumb method - create a loop and push the working end through the loop with your thumb.

Overhand method - create a bight, by twisting the hand over at the wrist, pinch the working end with your fingers and pull through the loop.